This application seeks partial support for a magnetic resonance imaging (MRI) and spectroscopy (MRS) instrument equipped with an ultrahigh magnetic field for in vivo studies of animal models. The proposed animal MRI/MRS instrument will be based on a horizontal 16.4 T magnet having a clear bore diameter of 26 cm, which will be the first of its kind in the nation. It will be located in the Center for Magnetic Resonance Research (CMRR), to take advantage of the high field MR expertise and infrastructure already in place and supported by the NIH. This ultrahigh field MR system will support and enhance research being conducted within a Biotechnology Research Resource grant (P41 RR008079), a Neuroscience Core Center grant (P30 NS057091), and numerous projects funded by R01 and other grants. Among its many new capabilities, this unique 16.4T MR system will provide increased spatial resolution (e.g., for imaging Alzheimer's plaques in mice), increased spatial resolution and specificity in fMRI (e.g., for mapping functional structures in the brain), and increased sensitivity and biochemical information in MRS (e.g., for understanding the coupling between brain function and energy metabolism). [unreadable] PUBLIC HEALTH RELEVANCE: Quantitative imaging is essential to understanding all types of brain diseases. In vivo MRS and MRI has contributed significantly to the current knowledge of normal and diseased brain, but the achievable sensitivity and resolution (spatial and spectral) are limited by the strength of the magnetic field. The proposed MRI/MRS instrument will offer a substantially increased magnetic field (16.4 T) over previous in vivo MR systems, and thus, will yield new structural, functional, and biochemical information in studies of normal brain and disease models. This knowledge, together with the advanced MRI and MRS techniques to be developed, will offer valuable tools for preclinical trials of novel therapeutic agents, and ultimately, for early disease detection and guiding treatments in the clinic. [unreadable] [unreadable] [unreadable]